Mental disorders as a predictor of incident edentulism: a prospective cohort study

Abstract

Edentulism represents the terminal stage of cumulative oral disease and is a key indicator of oral health deterioration in aging populations. Although individuals with mental disorders are recognized as a high-risk group for poor oral health, longitudinal evidence linking mental disorders to incident edentulism remains limited, particularly in non-Western populations. This study aimed to examine the prospective association between baseline mental disorders and incident edentulism over a 7-year follow-up period in a nationally representative cohort of Chinese adults aged 45 years and older. We conducted a prospective cohort study using data from the China Health and Retirement Longitudinal Study (CHARLS). A total of 11,719 participants with natural dentition at baseline (2011) were included. Mental disorders were assessed via self-reported physician diagnosis of emotional, nervous, or psychiatric conditions. The outcome was incident edentulism, defined as complete tooth loss at the 2018 follow-up. Survey-weighted logistic regression models were used to estimate associations, with sequential adjustment for demographic (age, sex), socioeconomic (education, residence), and behavioral factors (smoking status). Logistic regression was chosen due to the binary nature of the outcome and the absence of precise timing of edentulism onset. Results are presented as odds ratios (ORs) with 95% confidence intervals (CIs). Over the 7-year follow-up, 16% of participants developed edentulism. The incidence was higher among those with baseline mental disorders compared to those without (25% vs. 16%). In the fully adjusted model, mental disorders were significantly associated with an increased risk of edentulism (OR = 1.82, 95% CI: 1.20–2.76, p = 0.005). Older age and lower educational attainment were also significant predictors, while sex and smoking status were not significantly associated after full adjustment. Baseline mental disorders were independently associated with an increased risk of incident edentulism among middle-aged and older Chinese adults. These findings highlight the need for integrated oral and mental healthcare strategies. However, potential misclassification of exposure and outcome, as well as selection bias due to loss to follow-up, should be considered when interpreting the results.